The Fermi Paradox and the Aurora Effect: Exo-civilization Settlement, Expansion, and Steady States

  title={The Fermi Paradox and the Aurora Effect: Exo-civilization Settlement, Expansion, and Steady States},
  author={Jonathan J. Carroll-Nellenback and Adam Frank and Jason T. Wright and Caleb A. Scharf},
  journal={The Astronomical Journal},
We model the settlement of the Galaxy by space-faring civilizations in order to address issues related to the Fermi Paradox. We are motivated to explore the problem in a way that avoids assumptions about the agency (i.e., questions of intent and motivation) of any exo-civilization seeking to settle other planetary systems. We begin by considering the speed of an advancing settlement front to determine if the Galaxy can become inhabited with space-faring civilizations on timescales shorter than… 

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  • B. Lacki
  • Physics
    International Journal of Astrobiology
  • 2021
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